This post is for the people that just don't get it. Big time error on the part of the writers.
The plane should have been going to FIJI instead of LAX because at the point in time the plane crashed and did not crash is when space\time split so they were already off course.
@Tapestry: The thing is mate, it did split then. Do you understand what it means? A different outcome has happened at that point in time. The plane crashed at that single point in space\time and the plane did not crash at that point in space\time. two different outcomes at the same space in time is considered a parallel branch of time with 2 different outcomes. Tapestry, If you can't understand that, I don't have a clearer way to explain it to you.
You have to consider that we already know that the difference in the plane crashing and not crashing has an effect on the future so that my friend means an alternate time line has been created by the change in circumstances at that point in space\time. Now consider this, if the survivors were not on the island any longer and the events that the crash had set into motion were negated, we could simply say that the future has been changed but the alternate future from the point of the plane crash still exists.